Air purging apparatus for pumps



April 5, 1960 R. w. ERlKsoN l-:rAL 2,931,314

AIR PURGING APPARATUS FOR PUMPS med my 1v, 195s gnngpulllllllllllll l I"Y United States Patent O AIR PURGING APPARATUS FOR PUMPS Robert W.Erikson and William Ray Kiefer, Rockford, Ilhassigsnors to SandstrandCorporation, a corporation o mo Application May 17, 1955, Serial No.509,052

6 Claims. (Cl. 103-203) This application relates to a liquid pumpingsystem, and more particularly, to apparatus for purging air from an oilburner pump.

It is the general object of the present invention to produce a new andimproved air purging apparatus for pumps.

It is a more specific object of the present invention to provide an airpurging means for oil burner pumps, which is operable effectively topurge air entrapped in the oil burner system.

A feature of the present invention is the provision of a by-pass passageinterconnecting the high pressure discharge of an oil burner pump withthe intake of the pump, and to provide in said passage a by-pass valveeffective to close the passage when the pump is pumping air (therebypermitting the air to be expelled from the system), and in which theby-pass valve may be moved to a position opening the passage after airhas been purged from the system.

In our copending application, Serial Number 508,394 filed May 16. 1955,we disclosed and claimed an air purging system for oil pumps wherein thepurging means is positioned on the downstream or low pressure side ofthe pressure regulating valve which controls the pump burner port. Suchlocation of the air purging is necessary to the apparatus disclosed insaid copending application because of the provision in the pressureregulating valve of constantly open bleed slots interconnecting the highpressure discharge of the pump with the low pressure return so as topermit rapid closing of the valve. Because of this, air purging cannotbe elected with the pressure regulating valve shown in said copendingapplication by simply removing the plug for the gauge port as the effectof such removal would be to draw air into the system via the bleed slotsof the valve rather than expel air from the system.

According to the present invention, however, no bleed slots are providedin the pressure regulating valve, and thus no leakage path is providedthrough such valve, when it is in closed position. Because of theabsence of such leakage path, purging may be accomplished simply byremoving the plug for the gauge port.

As pointed out in our copending application, however, the bleed slotsprovided in the pressure regulating valve there shown perform animportant function, in that the valve may move rapidly to closedposition upon shutdown of the pump. A similar advantage is achieved withthe present invention, inasmuch as bleed slots or bleed passages areprovided in the pump between the high pressure discharge and the pumpreturn, although such bleed passages are provided elsewhere than in thepressure regulating valve.

The foregoing objects and advantages will be readily apparent from thefollowing description and drawings, in which:

Fig. l is a vertical sectional view through an oil burner pump embodyingthe present invention, and

Fig. 2 is a transverse sectional view taken generally 2,931,314 PatentedApr. 5, 1960 at the location of the line 2-2 of Fig. l and showing aslightly modified form of the invention.

While this invention is susceptible of embodiments in many diterentforms. there is shown in the drawings and will herein be described indetail several embodiments, with the understanding that the presentdisclosure is to be considered as an exemplificat'on of the principlesof the invention and is not intended to limit the invention to theembodiments illustrated. The scope of the invention will be pointed outin the appended claims.

While as previously noted, Figs. l and 2 of the drawing show modiliedforms of the present invention, both forms are embodied in an oil burnerpump, and thus parts which are common to both figures (and function inidentical manners) will be given similar reference numerals. Thus, thereis shown a pump 10 having a casing 1I enclosing a crescent type gearpump 12, whose intake 12a opens as through end plate 11a to a reservoir13 and whose high pressure outlet 12b in plate 11a communicates with apassage 12t` in plate lla, in tum connecting with a passage 12d incasing 11, which opens to a valve chamber 14 at one end of a bore 15formed in casing 11. A sleeve 16 is press fitted into the bore 15 andreciprocably carries a piston 17, having a valving portion 18 at one endcontrolling a discharge port 19 which communicates with the burner ofthe oil furnace. The sleeve 16 is provided with a plurality of slots 20opening at one end to the valve chamber 14 and at the other end to theouter face of the piston valve 17. The piston valve is provided with anannular ring 21 controlling a plurality of openings, such as the oneshown at 22, which communicate through the sleeve and with an annulargroove 23 formed on the exterior surface of the sleeve.

As pressure accumulates in the valve chamber 14 the pressure responsivevalve piston is moved to the left (as secn in Fig. 2) againt the bias ofits spring until the ring 21 uncovers the opening 22, therebyestablishing communication between the valve chamber 14 and the returngroove 23. The groove 23 opens into a return chamber 25 whichcommunicates via a port 26 with the reservoir 13.

As previously pointed out, the pressure regulating valve just describedis provided with no bleed slots or openings which provide or establish aconstant communication between the valve chamber 14 and the returngroove 23. Such bleed slots, however, are not omitted from the pumpstructure shown, but are included as a part of a by-pass systemhereinafter to be described.

Referring to the embodiment of the invention illustrated in Pig. 1,there is provided air purging means comprising a port 30 exposed to thehigh pressure discharge of the pump 12, which port is adapted to beopened and closed by a ball valve 31 urged to the position shown(closing port 30) by a spring 32. The spring has one end bearing againsta disk 33 secured in the casing, and at its other end bears against anopen-ended cylindrical member 34. The member 34 is provided along itsexterior surface with a plurality of bleed slots 35 and the disk 33 isprovided with a bleed opening 36.

On pump start-up, the spring 32 holds the ball 31 in a position closingthe port 30. In this position, no bleed slots are provided in thesystem, and air may be purged simply by removing the plug 50 from thegauge port normally provided in the casing (and hereinafter described).When the pump 12 begins to pump oil rather than air, the gauge port plugis replaced and then the increased pressure developed by the pump,acting against a portion of the ball 31, serves to unseat the ball andthus permit a bleed connection between the high pressure discharge ofthe pump, slots 35 and opening 36, into a by-pass passage 37 whichconnects at one end with a space 37a in the casing enclosing the seal 38for the pump shaft 39, which space in the casing is connected by asecond passage 40 with the annular return groove 23.

ln the embodiment of the invention shown in Fig. 2, the air purgingmeans comprises a by-pass valve located in the gauge port. As previouslynoted, the pump of the present invention is provided with a gauge port50 closed at its outer end by an exterior gauge plug 51. The gauge plugmay be solid or it may carry a suitable pressure gauge. Located withinthe gauge port is a by-pass valve 52 having cylindrical side walls 53controlling the end of a by-pass passage 54 opening into the gauge port.The passage 54 communicates at its other end with the return chamber 25.A spring 55 bears at one end against the pump casing and at its otherend against the by-pass valve 52 to urge the same against a snap ring 56located in the gauge port, and thus urges the valve 52 to move to aposition wherein the side walls 53 close the by-pass passage 54.

In the modification of Fig. 2, the gauge plug 51 is provided at itsinner end with a stem 57 of reduced diameter adapted to contact thevalve 52 and move the same to the position shown in the drawings(opening the by-pass passage 54) when the gauge plug is fully positionedin the casing. The end of the stem S7 which contacts the valve isslotted as at 57a to permit leakage of oil through an opening 59provided in the base 58 of the bypass valve.

In operation, when it is desired to purge air from the pump in Fig. 2,the gauge plug 51 is removed. When this occurs, the spring S moves theby-pass valve 52 downwardly (as seen in Fig. 2) to a position closingoff the by-pass passage S4. When this condition obtains and the pump isstarted, air in the system will be driven out the gauge port through theopening 59 and the opening left by removal of the plug 51. When air hasbeen purged from the system as evidenced by the appearance of oil, thegauge plug may be replaced and in replacing the plug, its stem willcontact the by-pass valve to move the same to a position uncovering oropening the bypass passage 54 and the small hole 59 in the by-pass valveprovides a bleed connection between the valve chamber 14 and the returnchamber 25.

From the foregoing, it will be seen that the air purging means of thepresent invention provides a system whereby purging can be accomplishedon the upstream or high pressure side of the pressure regulating valveand the air expelled out of the gauge port normally pro vided on oilburner pumps. This arrangement is possible, according to the presentinvention, while retaining in the pump the advantages of bleedconnections between the high pressure and low pressure side of the pump,with such bleed connections permitting the pressure regulating valve toclose rapidly. lt will be readily apparant to those skilled in the artthat the air purging apparatus of the present invention will be readilyadaptable for use in a one-line oil burner system of the type describedin said copending application.

We claim:

l. In an oil burner pump having a casing, a pump in the casing having alow pressure intake and a high pressure discharge, a burner port in thecasing, a passage in the casing connecting the high pressure dischargeand the burner port, and a pressure responsive valve in the passageadapted to establish communication between the high pressure dischargeand the burner port upon the build-up of a predetermined dischargepressure, air purging means comprising a purge port in the casing forconnecting said rst recited passage and the pump discharge toatmosphere, a closure plug removably positionable in the purge port, ableed passage in the casing in parallel with said pressure responsivevalve for establishing communication between the high pressure dischargeand said intake, a bleed valve controlling said bleed passage, and meansengaging and yieldably biasing the bleed valve to a first positionclosing said bleed passage when the closure plug is removed from thepurge port, said. bleed valve having a portion exposed to said highpressure discharge to be moved thereby to a second position opening thebleed passage when the closure plug is positioned to close the purgeport, said closure plug bcng removable on pump startup to permit purgingof air to atmosphere with said bleed valve closed, and said bleed valveopening on positioning the closure plug in the purge port to permitrapid closure of the pressure responsive valve on pump shutdown.

2. In an oil burner pump having a casing, a pump in the casing having alow pressure intake and a high pressure discharge, a gauge port in thecasing constantly exposed to said high pressure discharge, a burner portin the casing, a passage in the casing connecting the high pressuredischarge and the burner port, and a pressure responsive valve in thepassage adapted to establish cornmunication between the high pressuredischarge and the burner port upon the build-up of a predetermineddischarge pressure, air purging means comprising a by-pass passage inthe casing in parallel with the pressure responsive valve communicatingat one end with said intake and opening at its other end to said gaugeport, a bypass valve in the gauge port and movable to control saidopening, means biasing the by-pass valve to move to a first positionclosing said opening to close the by-pass passage, and a gauge plugthreadedly received in the cas ing gauge port and having a portionengageable with the by-pass valve to move it to a second positionopening the by-pass passage.

3. ln an oil burner pump having a casing, a pump in the casing having alow pressure intake and a high pressure discharge, a gauge port in thecasing constantly exposed to said high pressure discharge, a burner portin the casing, a passage in the casing connecting the high pressuredischarge and the burner port, and a pressure responsive valve in thepassage adapted to establish communication between the high pressuredischarge and the burner port upon the build-up of a predetermineddischarge pressure, air purging means comprising a by-pass passage inthe casing in parallel with the pressure responsive valve communicatingat one end with said intake and opening at its other end to said gaugeport, a bypass valve in the gauge port and movable to control saidopening, means biasing the by-pass valve to move to a first positionclosing said opening to close the bypass passage, a gauge plugthreadedly received in the casing and having a portion engageable withthe by-pass valve to move it to a second position opening the by-passpassage, and a bleed opening extending through the by pass valve toprovide restricted communication between the gauge port and the by-passpassage when said by-pass valve is in said second position.

4. In an oil burner pump having a casing, a pump in the casing having alow pressure intake and a high pressure discharge, a burner port in thecasing, a passage in the casing connecting the high pressure dischargeand the burner port, and a pressure responsive valve in the passageadapted to establish communication between the high pressure dischargeand the burner port upon the build-up of a predetermined dischargepressure, air purging apparatus including means in the casing providinga bleed passage in parallel with the pressure responsive valve andcommunicating at one end with the high pressure discharge of the pumpand communicating at its other end with the low pressure intake, valvemeans in the bleed passage movable to one position for closing saidbleed passage and movable to a second position for opening the bleedpassage, a purge port for connecting the first recited passage and thehigh pressure discharge to atmosphere, a closure plug removablypositionable in the purge port, means engaging and yieldably biasing thebleed valve means to closed position when the purge port closure plug isremoved, and means for opening the bleed valve means in response toplacement of the closure plug to close the purge port.

5. In an oil burner pumping mechanism having a casing, a pump in thecasing having a low pressure intake and a high pressure discharge, aburner port in the casing, a passage in the casing connecting the highpressure discharge and the burner port, and pressure responsive valvemeans in the passage adapted to establish communication between the highpressure discharge and the burner port upon the build up of apredetermined discharge pressure and adapted to establish communicationbetween the high pressure discharge and the low pressure intake upon thebuild up of a predetermined higher discharge pressure, air purgingapparatus comprising a bleed passage in parallel with the pressureresponsive valve means and communicating at one end with the highpressure discharge of the pump and communicating at its other end withthe low pressure intake, a valve member in said bleed passage movable toa first position for opening the bleed passage to establishcommunication between the high pressure discharge and the low pressureintake and movable to a second position for blocking the bleed passage,a purge port for connecting the rst recited passage and the highpressure discharge to atmosphere when said valve member is in thesecond, closed position, a closure plug removably mounted in the purgeport for closing the same, means engaging and yieldably biasing saidvalve member to closed position to block communication between the highpressure discharge and the low pressure intake through said bleedpassage when the closure plug is removed from the purge port to purgeair from the pump and means responsive to placement ofV the closure plugin purge port closing position for moving said valve member to openposition.

6. In an oil burner pumping mechanism having a casing, a pump in thecasing having a low pressure intake and a high pressure discharge, aburner port in the casing, a passage in the casing connecting the highpressure discharge and the burner port, and a pressure responsive valvemeans in said passage adapted to establish communication between thehigh pressure discharge and the burner port upon the build up of apredetermined discharge pressure and to also establish communicationbetween the high pressure discharge and the low pressure intake upon thebuild up of a higher predetermined discharge pressure, air purging meanscomprising a by-pass passage in the casing connected in parallel withsaid pressure responsive valve means and connecting the high pressuredischarge and the low pressure intake, a by-pass valve membercontrolling said by-pass passage, said bypass valve member having aportion exposed to said high pressure discharge to be moved thereby to aposition opening the by-pass passage, bleed means in said by-passpassage forming a restricted opening for bleeding oil through saidpassage only when lthe by-pass valve member is in open position, a purgeport in the casing for connecting said first recited passage and saidhigh pressure discharge to atmosphere, a closure plug removably threadedin the purge port for closing the port, and means engaging and yieldablybiasing the by-pass valve member to a position closing said by-passpassage when the closure plug is removed from the purge port to purgeair from the pump.

References Cited in the le of this patent UNITED STATES PATENTS2,071,800 Mock Feb. 23, 1937 2,123,950 Lattner July 19, 1938 2,149,969Lattner Mar. 7, 1939 2,159,720 Wahlrnark May 23, 1939 2,229,231Weyenberg Jan. 21, 1941 2,262,617 LOrange Nov. 11. 1941 2,346,398 Rohret al Apr. 11, 1944 2,442,361 Hulman June l, 1948 2,635,620 DeardorffApr. 2l, 1953 2,657,632 Kiefer Nov. 3, 1953 2,763,336 Erickson Sept. 18.1956 Disclaimer 2,931,314:.-R0bert W. Erikson and William Ray Kiefer,Rockford, IH. A TR PURGING APPARATUS FOR PUMPS. Putvnt dated Apr. 512H10. Disclaimer filed June 5, 1968, by the assignee, SandstrandCorpo/ution. Hereby enters this disclaimer to claims 4 and 5 of saidpatent.

[Oficial Gazette November 19, 1968.]

